Pluto really does seem to have captured people’s imagination.  With the announcement that the (dwarf) planet is larger than we thought, a neighbour was asking me how one measured its size.

This got me looking up some values in Pluto Is Larger Than Thought, Has Ice Cap, NASA Probe Reveals, from

The new measurement of Pluto is 1,473 miles (2,370 kilometers) across

The previous estimate from Earth was 1,430 miles (2,301 km).

Pluto does not meet the definition of a planet but as we will see that does not diminish it.  Far from a random and uninteresting chunk of ice, with little local gravitational influence on it’s neighborhood, it is an example of binary planetoids with tantalizing features. 


ET phone Earth!

We could be on the verge of answering one of the essential questions of humanity that has captivated our minds for centuries.

There may be far fewer galaxies further out in the Universe then might be expected, suggests a new study based on simulations and published this week in the Astrophysical Journal Letters.

The simulations show the first results from the Renaissance Simulations, a suite of extremely high-resolution adaptive mesh refinement (AMR) calculations of high redshift galaxy formation and hundreds of well-resolved galaxies. 

"Most critically, we show that the ultraviolet luminosity function of our simulated galaxies is consistent with observations of redshift galaxy populations at the bright end of the luminosity function, but at lower luminosities is essentially flat rather than rising steeply," wrote researchers in their paper. 

It is well known that muscles need resistance (gravity) to maintain optimal health, and when they do not have this resistance, they deteriorate. A new report published in the July 2015 issue of The FASEB Journal, however, suggests that this might not be true for all muscles, offering hope that there may be ways to preserve muscle mass and strength for individuals in low-resistance environments, whether it be the microgravity of space, extended periods in a hospital bed, or a 9-5 job behind a desk.

MarsPolar, a newly created international venture has started raising funds for their bold project to establish a permanent human colony on Mars. The team behind the project wants to collect at least $100.000 to cover the initial costs of their future endeavor.

Today, 30th June is asteroid day, to raise awareness of the searches astronomers do to detect and eventually deflect asteroids. This is your chance also to actually do something about them by signing the 100x petition (which has been signed by many famous astronomers and astronauts).

An asteroid impact is one of the few natural events we can actually prevent with our technology (unlike volcanoes, earthquakes and tsunami). With a few years or decades of warning, we can deflect them rather easily. But to find them in good time, first we need to detect them.

So, you are invited to a dinner by extraterrestrial hosts. Do you accept the invitation? And if so, which foods and beverages would be safe to eat? And, could you actually live long term on ET food? Or the other way around, if you have an ET guest, what food could you safely serve for them to eat?

First, it's not likely that you would enjoy a dinner served in a sauce of liquid nitrogen or liquid methane :). So, let's assume that they are organic carbon based lifeforms from an Earth-like world or at least an environment with Earth type temperatures and conditions (including perhaps living in oceans of icy moons).

Over the past week, ESA's Integral satellite has been observing an exceptional outburst of high-energy light produced by the black hole V404 Cygni that is devouring material from its stellar companion in our Milky Way galaxy, almost 8000 light-years away in the constellation Cygnus, the Swan.

Astronomers expect that galaxies grow by swallowing smaller galaxies. But the evidence is usually not easy to see -- just as the remains of the water thrown from a glass into a pond will quickly merge with the pond water, the stars in the infalling galaxy merge in with the very similar stars of the bigger galaxy leaving no trace. But now a team of astronomers led by PhD student Alessia Longobardi at the Max-Planck-Institut für extraterrestrische Physik , Garching, Germany has applied a clever observational trick to clearly show that the nearby giant elliptical galaxy Messier 87 merged with a smaller spiral galaxy in the last billion years.